(CNN) -- An explosion at an office and industrial complex in Menlo Park, California, killed one person late Friday afternoon, officials said.
Another person was injured and 23 others checked for possible injuries after the explosion at Membrane Technology and Research Inc., said Menlo Park Fire Chief Harold Schapelhouman.
The explosion was caused after a a mixture of liquid methane, helium and nitrogen ignited, Schapelhouman said.
When firefighters arrived, a severely injured man was found in a hallway of the facility and an injured woman was found near a door.
The man was rushed to a hospital but he died, Schapelhouman said. The woman had been "blown out of the door," and she was also rushed to a hospital, Schapelhouman said.
The explosion happened at 4:07 p.m. PT, CNN affiliate KGO said. There were concerns about hazardous materials at the scene, KGO reported.
The company website describes Membrane Technology and Research as a "world leader in the development and production of membrane-based separation systems for the petrochemical, natural gas and refining industries."
CNN's Marlena Baldacci and Greg Morrison contributed to this report.